Operation mode setting apparatus for air conditioner

ABSTRACT

An operation mode of an air condition is automatically set during an intermediate season so that the set operation mode can match the actual sensation of a user. A plurality of temperature zones are set defining a plurality of room-temperature ranges and a respective plurality of outside-temperature ranges, and operation modes are selectively assigned to each of the temperature zones. An operation mode is set according to the zone containing an actual room temperature and outside temperature. In addition, the temperature zones assignments are selectively changed according to a calendar date of operation.

BACKGROUND OF THE INVENTION

The present invention relates to the automatic setting of an operationmode of an air conditioner which is capable of a cooling operation, aheating operation and a dehumidifying or drying operation.

In order to realize automatic setting of an operation mode, it has beenproposed to automatically set a cooling operation or a heating operationaccording to whether a room temperature or an outdoor temperature ishigher or lower than a set value. However, none of the prior art deviceshas yet to succeed in realizing optimum settings during an intermediateor transitional period of the four seasons of a year.

An attempt has been made to overcome the problems encountered to theprior art devices described above, as disclosed in Japanese PatentPublication No. 63-150550/1988 (unexamined), in which a plurality oftemperature zones A to L are set by using a plurality ofroom-temperature set values and a plurality of outdoor-temperature setvalues freely and, for example, temperature zone A is assigned to a zonefor setting a heating operation, temperatures K, G and H are assigned toa zone for setting a dehumidifying (or drying) operation, a temperaturezone L is assigned to a zone for setting a cooling operation, and theother zones are assigned to a supervising zone which is a zone fordetecting a room temperature at predetermined time intervals. In thisprior art, any one of these temperature zones is determined to be themost suitable one according to a room temperature and an outdoortemperature, and a desired operation mode is automatically selected onthe basis of this result of the determination.

Japanese Patent Publication No. 63-306344/1988 (unexamined) shows adevice for determining any one of the four seasons by using roomtemperature and date information. The determination of a season isnormally made on the basis of the date information, and during atransitional period (that is, a period having unstable conditionscorresponding to a plurality of seasons in which temperature conditionsare not stable), the determination of a season is made by measuring themaximum and minimum temperatures of the day.

However, in any of the prior art devices described above, it isdifficult to achieve accurate selection during an intermediate period,such as spring and autumn, if automatic selection is executed from amongthe cooling operation, heating operation and dehumidifying operation.

When a plurality of temperature zones are set and automatic selection ofan operation is executed, a problem arises in that the temperaturesensation (or feeling) of a user varies depending on spring or autumneven within the same temperature zone. More specifically, usersgenerally feel cold in spring and desire heating, but in autumn, feelhot and desire cooling, even when the same temperature zone is selectedin spring and autumn. It is, therefore, quite difficult to realize anoptimum automatic selection merely by the setting of temperature zones.

Another problem arises in that if a determination of a season is made,the result of the determination does not always correspond to a desiredoperation mode and, particularly in summer, it is difficult to determinean accurate timing at which switching from the dehumidifying operationis to be executed to the cooling operation.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a new operation-modesetting apparatus for setting an optimum temperature zone during theintermediate period of seasons such as spring and autumn.

According to the present invention, there is provided an operation-modesetting apparatus for an air conditioner, which automatically sets oneof operation modes including a cooling mode, a heating mode and adehumidifying mode. The operation-mode setting apparatus has a zonesetting part for determining a plurality of temperature zones from aplurality of room temperature set values and a plurality of outdoortemperature set values, a first zone assignment part for assigning eachzone to a zone for setting a cooling mode, a zone for setting a heatingmode, a zone for setting a dehumidifying mode and another zone, and asecond zone assignment part for assigning, on the basis of a dateinformation, the aforesaid other zone to a zone for setting any one of acooling mode, a heating mode and a dehumidifying mode, whereby a desiredoperation mode is automatically set by detecting the room temperatureand the outdoor temperature.

There is also provided an operation-mode setting apparatus for executingautomatic selection from among operation setting of an air conditionerfor carrying out a cooling operation, a heating operation and adehumidifying operation. This apparatus has a zone setting part forsetting a plurality of temperture zones from a plurality ofroom-temperature set values and a plurality of outdoor-temperature setvalues, a first zone assignment part for assigning each zone to a zonefor setting a cooling operation, a zone for setting a heating operationand another zone, and a second zone assignment part for dividing theaforesaid other zone into a plurality of zones on the basis of outdoortemperatures, and assigning, on the basis of a date information, each ofdivided plurality of the zones to a zone for setting any one of acooling operation, a heating operation and a dehumidifying operation,whereby a desired operation mode is automatically set by detecting theroom temperature and the outdoor temperature.

The operation-mode setting apparatus in the present invention asdescribed above changes operation modes of part of the temperature zoneson the basis of the date of a calendar.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of an electric circuit of an air conditionerembodying the present invention,

FIG. 2 is a diagram showing essential operational steps of the airconditioner shown in FIG. 1,

FIG. 3 is an explanatory diagram showing temperature zones based on roomtemperatures and outdoor temperatures, and

FIG. 4 is a diagram showing an operation for setting an operation mode.

PREFERRED EMBODIMENTS OF THE INVENTION

Referring first to FIG. 1, a 100-V commercial AC power source 1 suppliesAC power to a room unit and an outdoor unit. A varistor 2 serves toabsorb a surge voltage. A coil 3 and a choke coil 4 constitute a noisefilter in combination with the varistor 2. A diode bridge 5 serves toperform full-wave rectification of a single-phase commercial alternatingcurrent and output the resultant current to an inverter bridge 6. Duringthis full-wave rectification, an AC voltage having an effective value of100 V is converted into a DC voltage of approximately 280 V by a voltagedoubler rectifier circuit 7, and the DC voltage of approximately 280 Vis supplied to the inverter bridge 6. This inverter bridge 6 is made upof six switching elements which are connected in three-phase bridgeform, and each of the switching elements is switched on/off on the basisof a PWM theory to output a three-phase pseudo-sine wave to a compressor8.

A direct current detection circuit 9 converts an alternating currentdetected by a DC transformer (CT) 10 into a direct current and appliesthe direct current to an A/D (analog/digital) input port of amicroprocessor 11. The microprocessor 11 corrects the frequency of thepseudo-sine wave to be supplied to the compressor 8 so that the currentdetected by the current detection circuit 9 does not exceed apredetermined current.

A temperature sensor 12 detects a temperature of the compressor 8. Themicroprocessor 11 receives a sensor output indicative of thistemperature via a temperature detection circuit 32 and, as in the caseof the current detection described above, corrects the frequency of thepseudo-sine wave to be supplied to the compressor 8 so that thetemperature does not exceed a predetermined temperature.

An interface 13 serves to establish communication of data between themicroprocessor 11 of the outdoor unit and a microprocessor 20 of theroom unit. The room unit transmits signals such as an operation signalindicative of a cooling operation, a heating operation or adehumidifying operation and a signal which serves to determine thefrequency of the three-phase pseudo-sine wave to be supplied to thecompressor 8. The interface 13 also serves to transmit, to the outdoorunit, data such as data indicative of a temperature detected by anoutdoor-temperature sensor 19 and data indicative of the occurrence ofan abnormality.

A signal amplifying circuit 14 electrically amplifies an on/off signaloutputted from the microprocessor 11 up to a magnitude which permitsdriving of the switching elements of the inverter bridge 6. A switchingsignal based on the PWM theory is generated by the microprocessor 11 onthe basis of a frequency signal.

A relay 15 and a phototriac 16 are controlled by the microprocessor 11.Reference numeral 17 denotes a four-way valve and reference numeral 18 afan for an outdoor heat exchanger. A refrigerant cycle for the coolingoperation and a refrigerant cycle for the heating operation are switchedby switching the four-way valve 17. The rotating speed of the fan 18 isvaried with a variation in outdoor temperature by varying the firingangle of the phototriac.

A microprocessor 20 provides control over the outdoor unit. Themicroprocessor 20 transfers data to/from the microprocessor 11 via theinterface 21. A normally open contact 22 is opened or closed undercontrol of a relay 23. When an air-conditioning operation is to beperformed, the microprocessor 20 energizes the relay 23 to close thecontact 22, thereby supplying electric power to the outdoor unit. Whenthe contact 22 is open, the interface 21 simultaneously shuts off signaltransfer so that no signal is transmitted to the outdoor unit.

A room-temperature sensor 24 detects the temperature of a room to beair-conditioned. The microprocessor 20 obtains a value indicative of theincreased or decreased amount of the frequency of the pseudo-sine waveto be supplied to the compressor 8, from a desired temperature and thetemperature detected by the room-temperature sensor 24, and thentransmits a corresponding new frequency signal to the outdoor unit. Amethod of obtaining the value indicative of the increased or decreasedamount of frequency is selected from among PID control, fuzzy controland the like.

An input circuit 25 permits setting of operation data. During the use ofa wireless remote controller or the like, the operation data istransmitted from the wireless remote controller as a wireless signal andreceived by the input circuit 25.

A fan motor 26 is provided for air supplying, and a motor 27 is fordriving a flap (not shown) which serves to change the direction of airstream. The fan motor 26 and the motor 27 are controlled by motorcontrollers 28 and 29, respectively. A power supply circuit 30 suppliesDC power to the room unit.

The microprocessor 20 controls the rotating speed of the fan motor 26and the rotating angle of the flap driving motor 27. A clock and acalendar are incorporated into the microprocessor 20 as an internalprogram. Each time the clock counts one day, the date is set forward byone day. If the power supply is turned on and an initial value is set,the microprocessor can function as a clock and a calendar.

In FIG. 2 showing the essential operational steps of the air conditionerarranged in the above-described manner, the operation of the airconditioner is started in Step S1. In Step S2, various data arereceived, such as outdoor temperature data from the outdoor unit,frequency data for driving the compressor 8, defrosting data, andabnormality data indicative of the kind and nature of abnormality if itoccurs in the outdoor unit. Furthermore, during the use of the wirelessremote controller, if a wireless signal transmitted from the wirelessremote ccntroller is received, the received wireless signal is inputtedinto the microprocessor 20.

In Step S3, it is determined whether setting (or changing) of anoperation mode is needed. If it is determined that setting of theoperation mode is needed, the operation mode is set in Step S4. Typicalexamples of the case where it is determined that setting of theoperation mode is needed are: when the operation of the air conditioneris initially started with the automatic selection of the operation modebeing set by a switch or the like; when the operation of the airconditioner is started after the air conditioner is continuously placedin its inoperative state for two hours or more (i.e., when changing ofthe operation mode must be performed); and when the mode setting of theair conditioner changes from a manual operation mode to an automaticoperation mode if the air conditioner is operated under remote control(HA input).

In Step S5, a frequency value to be transmitted to the outdoor unit iscalculated from a room temperature and a desired temperature. In StepS6, If it is determined that any abnormality has occurred in the airconditioner, a required processing is executed. In Step S7, setting ofthe room unit is performed, that is, the rotating speed of the fan motor26 and the rotating angle of the flap-driving motor 27 are determined.

In Step S8, data are transmitted to the outdoor unit, such as operationmode data for controlling the on/off operation of the four-way valve 17(i.e., data indicative of any of the cooling operation, the heatingoperating and the dehumidifying operation), and frequency data for apseudo-sine wave to be supplied to the compressor 8.

In FIG. 3 which shows temperature zones used in determining theoperation mode in Step S4, a plurality of room-temperature set valuesTR1 and TR2 and a plurality of outdoor-temperature set values are usedto set a plurality of temperature zones. The temperature zones are setin a virtual space of a computer program in accordance with a zonesetting program (a zone setting part) of the microprocessor 20. Thetemperature zones are determined as a zone C (a zone for setting acooling operation), a zone H (a zone for setting a heating operation)and zones Z0 to Z5 (other zones) in the virtual space in accordance witha zone assignment program (a first zone assignment part). The zones Z0to Z5 are reassigned to any one of the zones including a zone forsetting the cooling operation, a zone for setting the heating operation,and a zone for setting an operation which provides a dehumidifyingeffect (such as dehumidifying operation utilizing a reheating device ora drying operation utilizing a reheating device or a drying operationwhich carries out simple dehumidification by intermittently driving anindoor fan) in accordance with a zone assignment program (a second zoneassignment part) which runs on the basis of a date (data indicative of amonth and a day cumulatively calculated by and stored in themicroprocessor 20). For example, (1) if the date stored in themicroprocessor 20 falls in the months from May to October, the zones Z0to Z5 are selected as zones for setting the drying operation; and (2) ifthe date stored in the microprocessor 20 falls in the months fromNovember to April, the zones Z0 and Z1 are selected as zones for settingthe drying operation, while the zones Z2 through Z5 are selected aszones for setting the heating operation.

By dividing one year into two periods in the above-described manner, itis possible to set temperature zones which permit drying operation orthe cooling operation to be primarily selected during the relatively hotperiod between May and October, as well as temperatutre zones whichpermit the heating operation to be primarily selected during therelatively cold period between November and April. Accordingly, it ispossible to set an operation mode which matches the actual sensation orfeeling of a user.

FIG. 4 is a diagram showing an operation which executed to set anoperation mode by using the temperature zones shown in FIG. 3. In StepS41, a room temperature and an outdoor temperature are inputted. Theroom temperature is a temperature detected by the room-temperaturesensor 24, and the outdoor temperature is a temperature detected by theoutdoor-temperature sensor 19 of the outdoor unit. The outdoortemperature is transmitted as data from the microprocessor 11 to themicroprocessor 20. In Steps S42 to S44, it is determined whichtemperature zone corresponds to the room temperature and the outdoortemperature. If it is determined that the zone C corresponds to the roomtemperature and the outdoor temperature, the process proceeds to StepS48, where the cooling operation is set. If it is determined that thezone H corresponds to both the room and outdoor temperatures, theprocess proceeds to Step S46, where the heating operation is set. If itis determined that the zone Z0 or Z1 corresponds to both temperatures,the process proceeds to Step S47, where the drying operation is set. Ifany of the remaining zones corresponds to both temperatures, the processproceeds to Step S45, where it is determined whether the current date isbetween May and October. If the current date is between May and October,the process proceeds to Step S47, where the drying operation is set. Ifthe current date is between November and April, the process proceeds toStep S46, where the heating operation is set.

The manner of assignment of the zones Z0 to Z5 and the manner of datesetting are not limited to the examples explained above. For example,one year may be divided into six periods or seasons such as winter,spring, a rainy season, summer, autumn and early winter, and theassignment of the zones Z0 to Z5 may be altered for each season so thatit is possible to obtain temperature zones optimum for each individualseason.

Although in the present embodiment the date used for setting anoperation mode is calculated by and stored in the microprocessor 20 ofthe room unit, date information may be calculated by and stored in thewireless remote controller so that the date information is transmittedto the room unit. The date information may also be visually displayed onthe wireless remote controller.

As described above, in the operation-mode setting device of an airconditioner according to the present invention, a plurality oftemperature zones are set by using a plurality of room temperature setvalues and a plurality of outdoor temperature set values. By determiningwhich temperature zone coressponds to the actual room temperature andoutdoor temperature, a cooling operation, a heating operation and adehumidifying operation are selectively set according. In addition, thetemperature zones are arranged so that the operation modes are changedaccording to the calendar date. Accordingly, the manner of selectivesetting of the operation modes which is based on the temperature zonescan be modified in accordance with a date so that the cooling operationor the heating operation can be preferentially selected. It is,therefore, possible to automatically change temperature zones inaccordance with the actual sensation of a user so that the heatingoperation and the cooling operation can be preferentially selected inspring and in autumn, respectively. Accordingly, it is possible toprovide an arrangement capable of setting an optimum operation modethroughout the year.

What is claimed is:
 1. An operation mode setting apparatus for an airconditioner, said apparatus for setting any one of plural operationmodes of the air conditioner, said operation modes including a roomcooling mode for cooling a room, a room heating mode for heating saidroom and a room dehumidifying mode for dehumidifying said room, saidapparatus comprising:room temperature detection means for detecting atemperature of said room; outdoor temperature detection means fordetecting an outdoor temperature; date information generating means forgenerating date information indicative of a calendar date uponinitiation of a starting operation of said air conditioner; zone settingmeans for determining a plurality of temperature zones, each of saidplurality of temperature zones being defined by a room temperature rangeand an associated outdoor temperature range; zone marking means formarking at least one of said plurality of temperature zones as a coolingmode zone, for marking at least one other of said plurality oftemperature zones as a heating mode zone, and for marking at least aremaining one of said plurality of temperature zones as a dehumidifyingmode zone; changing means for changing the marking of at least one ofsaid plurality of zones from said dehumidifying mode zone to one of saidcooling mode zone and said heating mode zone in accordance with saiddate information; and operation mode setting means for automaticallysetting the operation mode of the air conditioner in accordance with themarking of a temperature zone containing the room temperature detectedby said room temperature detecting means and the outdoor temperaturedetected by said outdoor temperature detecting means.